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Universal Ensemble-Embedding Graph Neural Network for Direct Prediction of Optical Spectra from Crystal Structures
Nguyen Tuan Hung1,2, Ryotaro Okabe2,3, Abhijatmedhi Chotrattanapituk2,4
1Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, 980-8578, Japan.
A new machine learning model, GNNOpt, accurately predicts optical properties of solids using graph neural networks. This breakthrough enables efficient discovery of advanced materials for solar cells and quantum technologies.
Area of Science:
- Solid-state physics
- Materials science
- Computational chemistry
Background:
- Optical properties are crucial for applications like solar panels and sensors.
- First-principles computation of these properties is computationally expensive and complex.
- Machine learning shows promise but lacks efficient methods for optical property prediction from crystal structures.
Purpose of the Study:
- Introduce GNNOpt, an equivariant graph neural network for predicting optical spectra.
- Enable high-quality optical property predictions with a limited dataset.
- Facilitate the screening of photovoltaic and quantum materials.
Main Methods:
- Developed GNNOpt, an equivariant graph neural network with universal embedding.
- Utilized Kramers-Krönig relations for predicting various optical properties.
- Trained the model on a dataset of 944 materials.
- Validated predictions with first-principles calculations.
Main Results:
- GNNOpt achieves high-quality predictions of optical properties, including absorption, dielectric function, refractive index, and reflectance.
- The model demonstrates excellent agreement with first-principles calculations for unseen materials.
- Successfully screened photovoltaic materials and identified potential quantum materials, like SiOs.
Conclusions:
- GNNOpt offers an efficient and accurate approach for predicting optical properties from crystal structures.
- The model accelerates the discovery of novel materials for diverse technological applications.
- Highlights the potential of graph neural networks in materials science and condensed matter physics.
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